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I'd accidentally introduced these typos in ea415610 (hooks/docs: Add oci-hooks.5 and per-package man page building, 2018-05-15, #772). Signed-off-by: W. Trevor King <wking@tremily.us> Closes: #810 Approved by: mheon
23 lines
1.8 KiB
Markdown
23 lines
1.8 KiB
Markdown
# OCI Hooks Configuration
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For POSIX platforms, the [OCI runtime configuration][runtime-spec] supports [hooks][spec-hooks] for configuring custom actions related to the life cycle of the container.
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The way you enable the hooks above is by editing the OCI runtime configuration before running the OCI runtime (e.g. [`runc`][runc]).
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CRI-O and `podman create` create the OCI configuration for you, and this documentation allows developers to configure them to set their intended hooks.
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One problem with hooks is that the runtime actually stalls execution of the container before running the hooks and stalls completion of the container, until all hooks complete.
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This can cause some performance issues.
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Also a lot of hooks just check if certain configuration is set and then exit early, without doing anything.
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For example the [oci-systemd-hook][] only executes if the command is `init` or `systemd`, otherwise it just exits.
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This means if we automatically enabled all hooks, every container would have to execute `oci-systemd-hook`, even if they don't run systemd inside of the container.
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Performance would also suffer if we exectuted each hook at each stage ([pre-start][], [post-start][], and [post-stop][]).
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The hooks configuration is documented in [`oci-hooks.5`](docs/oci-hooks.5.md).
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[oci-systemd-hook]: https://github.com/projectatomic/oci-systemd-hook
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[post-start]: https://github.com/opencontainers/runtime-spec/blob/v1.0.1/config.md#poststart
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[post-stop]: https://github.com/opencontainers/runtime-spec/blob/v1.0.1/config.md#poststop
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[pre-start]: https://github.com/opencontainers/runtime-spec/blob/v1.0.1/config.md#prestart
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[runc]: https://github.com/opencontainers/runc
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[runtime-spec]: https://github.com/opencontainers/runtime-spec/blob/v1.0.1/spec.md
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[spec-hooks]: https://github.com/opencontainers/runtime-spec/blob/v1.0.1/config.md#posix-platform-hooks
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